Tool for cleaning and deepening grooves in pistons



Mamh 1, 1938 H. A. BERKMAN TOOL FOR CLEANING AND DEEPENING GROOVES IN PISTONS Filed Oct. 14, 1935 Patented Mar. l, 1938 mass:

TOOL FOR CLEANING AND GROOVES IN PISTON Herbert A. Berkman, Zim Manufacturing 7 of Illino Application October 14, 1935, Serial No. 44,822

the tool, all but a fra member being omitte either an edge view thereon, with the fra tion on line 4-- l of tion on line 5 of scale.

In the drawing I have DEEPENING S Chicago, 111., assignor to Company, a corporation 8 Claims.

The present invention relates to tools for cleaning out the grooves in the combustion engines, and, away metal to deepen the 5 of the present invention is to improve the cohstruction and operation of tools of this character and, particularly, to make it possible to scrape the bottoms of or deepen grooves in the modern pistons that are composed of comparatively soft metal, without danger of gouging or digging into the metal of the pistons.

A further object of th to produce a simple a specified, in which be most advantage d; Fig. 4 may be said to be f the carriage and theparts me bar in section, or a.sec- Fig.3; and Fig. 5 is a sec- Fig. 1, on a much larger grooves. The object 7 illustrated only a. single, simple embodiment of my invention and, for the sake of brevity, shall confine the detailed description thereto; although it will be understood that the plan of my invention maybeutilized in constructions differing widely from each other. Referring to the drawing, 1 represents a long flat steel bar bent edgewise, as indicated at 2,. into a large V. Thisbar forms what may be termed the frame or body of the tool or instrument, comprising a V-shaped seat or bearing to engage a piston while lying in a p ane at right angles to the axis of the piston, together with a straight member projecting from the end of one of the arms of the V; this straight member lying parallel to a' line bisecting the angle of the V. The bearing member may be engaged with a large piston, such as indicated or with a small piston such as indicated at a in Fig. l, or with apiston of any intermediatesize. It will be seen that the axes of the entire range. of pistons 'all he in a single plane which contains the line bisecting the angle of the V. v Mounted on the straight end portion of the bar I, which also serves as the operating handle, so as to be. slidable lengthwise thereof, is a suite present invention is nd novel tool of the type the cutting edge will always ously located for making a clean cut, regardless of the'size of the piston on which the work is being done.

I attain the ends sou features of constructi to con may be termed the axis or center line of the bearing seat. Thus, if the bearing seat is V-shaped, the carrier for the cutter is #0 mounted so that it will mo bisecting the V in diameter of the piston that is engaged in the seat able carrier 3 that may be locked in a fixed posi- 5 the cutting edge of the tool W111 come in contact tion at any point by means of a set screw 6.

hinge pin 5 positioned of the body or frame, element. This holder Hinged to the carrier, by a at right angles to the plane is a holder 6 for the cutter 'is in the form of a strong rigid arm whose free end extends into the vicinity of the line bisecting the angle of the V. At the free end of the holder is a disk-like head i lying at right angles to the long axis of the holder; A suitable cutter 8 lies against and is held to the outer face of this head. In the arrangement shown, this cutter element is a ring-like member having a series of radial blades 9 of different widths projecting therefrom. A screw It having a large head, passes through the center of the cutter element and into the holder. The head of the holder is cut away on the side toward the bearing or seat member'2 so that one of the blades of the cutter mayproject beyond the head in this-zone and be adapted to enter a groove in a piston clamped, as it'were, between the member 2 and the holder. 1

center point.

The various features invention is characteri pointed out with particu of novelty whereby my Zed will hereinafter be larity in the claims; but, for a full understanding of my invention and of its objects and advantages, reference may be had to the following detailed description taken in connection with the accompanying drawing, wherein:

Figure l is a plan view of one of my improved tools applied to a piston, the tool as a whole and a large piston being shown in large full lines, and asmall piston and the. seat or hearing therefor shifted to accommodate it being shown in dotted lines; Fig. 2 is an edge view of the tool and the upper part of the large piston shown in Fig. 1; Fig. 3 is a view showing the carrier member and the parts mounted thereon in section on a plane at right angles to the axis of a piston engaged in at A in Figs. 1 and 2 gment of the body or frame I The largest diameter of the cutter is less than the diameter of the head, so that the head will serve as a guard for all of the radial cutting elements except the one which is in a working position and for which the piston serves as a guard while the tool is being operated. It is not necessary to rely on the screw ID to hold the cutter against rotation. In the body portion of the cutter, between each pair of consecutive blades, is a notch ll. Projecting from the face of the head 1 is a pin [2 which fits into whichever notch in the cutter happens to register with the same. Whenever the cutter is to be adjusted to bring a particular blade into working position, the screw H1 is loosened. Then the cutter is lifted clear of the pin and is turned until the desired blade projects beyond the mutilated part of the head. The cutter is then re-engaged with the pin and the screw is tightened to clamp the cutter against the head. Associated with the holder 6 is what may be termed a shoe l4 that is adapted to rest against the periphery of a piston positioned in the tool. close to the cutter. This shoe is pro vided with a pair of arms [5 that extend along the holder, above and below the latter, to the hinge pin 5 with which they are engaged. Consequently, the shoe may swing back and forth with the holder, as a single unit. The holder is provided with a set screw it passing through the same and having its inner end engaged with the shoe. It will be seen that when the shoe is resting against a cylinder, as in Fig. 1, the turning of the screw it in one direction will lift the cutter out of the groove in the cylinder whereas, when the screw is backed off, the blade is permitted to move into the groove until the screw engages with the shoe. Thus, the shoe determines the distance to which a blade may penetrate a groove in a piston and the depth of out which may be made in the bottom of the groove, if cutting is to be done.

Means must be provided to hold the cutter in working relation to the piston while the tool is swung about the axis of the latter. The pressure on the cutter should be a yielding one, particularly since pistons are usually not true cylinders. Such yielding pressure is provided by a spring I! disposed between what may be termed the rear edge of the holder and an arm or bracket l8 projecting from the body of the carriage behind the holder.

In the use of the tool, the carriage is shifted outwardly along the straight portion or handle of the frame or body member, until a piston can be freely introduced between the holder and the V-shaped member. The protruding blade of the cutter, and the V-shaped body member lying in the same plane, both may be entered in a groove which is to be cleaned or deepened. This is accomplished by bringing the V-shaped member and the blade that is in working position into the plane of the groove and then producing a relative sliding movement between the frame or body and the carrier until the piston is yieldingly clamped between the V-shaped member and the shoe M. The set screw it is then adjusted to locate the cutting edge of the blade in working position at the proper depth below the surface of the piston. The tool is then swung around on the piston, about the axis of the latter, the blade cleaning out the groove and, if desired, making it deeper. Where increase in depth of a groove is desired, this increase need not be effected by a single cut, but the set screw l6 may be adjusted after each turn or two of the tool to enable the cutting edge to penetrate a little deeper after each adjustment.

The carrier has thereon a projecting ledge or shoulder l9 which engages with the front edge of the holder when the tool is empty, so that the holder will always remain approximately in what may be termed its working position; being held against the ledge or stop shoulder by the spring. Of course, when the tool is applied to a piston, the carrier must be shifted far enough in the direction of the latter to swing the holder clear of the ledge or shoulder, whereby the duty of serving as a stop devolves beyond the shoe M which now bears on and is yieldingly pressed against the piston.

While I have illustrated and described with particularly only a single preferred form of my invention, I do not desire to be limited to the exact structural details thus illustrated and described; but intend to cover all forms and arrangements which come within the definitions of my invention constituting the appended claims.

I claim:

1. In a tool for operating on pistons, a frame comprising a V-shaped member and a second member projecting from the free end of one arm of the V and lying parallel to a line bisecting the angle of the V, a carrier supported on and adjustable lengthwise of said second member, a tool movably mounted on said carrier, with its working end near said line, an adjustable stop device for the tool adapted to ride on the periphery of a piston engaged in the angle of said V-shaped member, and means on the carrier yieldingly to press the tool and said stop device against the piston.

2. A tool of the character described, comprising a member having a seat to engage the periphery of a piston, a tool, a carrier adjustable on said member from and toward said seat and supporting said tool, means on the carrier yieldingly to press the tool against a piston in said seat, an element movably mounted on the carrier and adapted to ride on the piston, and adjustable stop means between the tool and said element to transmit the pressure on the tool to the said element and limit the depth to which the tool can penetrate below the outer surface of the piston.

3. In a tool for operating on pistons, a member provided with a seat to engage the periphery of a piston, a carrier on said member adjustable from and toward said seat, a tool holder mounted on the carrier for movements thereon from and toward a piston engaged with said seat, means on the carrier yieldingly pressing the tool holder toward the said seat, and adjustable stop means associated with the holder and adapted to ride on the periphery of the piston.

4. In a tool for operating on pistons, a member provided with a seat to engage the periphery of a piston, a carrier on said member adjustable from and toward said seat, a tool holder mounted on the carrier for movements from and toward a piston engaged with said seat, means yieldingly pressing the tool holder toward the said seat, a movably-mounted element adapted to ride on the periphery of the piston, and an adjustable member on the holder and engaged with said element to limit the movement of the holder toward the piston.

5. In a tool for operating on pistons, a member provided with a seat to engage the periphery of a piston, a carrier on said member adjustable from and toward said seat, a tool holder hinged at one end to the carrier for swinging movements resting against the latter, and a stop shoulder from and toward a piston engaged with said seat, on the carrier against which the holder is held means yieldingly pressing the tool holder toward near its working position while the tool is empty. the said seat, a shoe hinged to the carrier to 7. In a piston groover and scraper, a bar cmswing about the hinge axisof the holder and prising a straight portion and a gooseneck, a 5 adapted to ride on the periphery of the piston, sleeve slidable on the straight portion of said bar, and an adjustable member on the holder engaged a cutter arm pivoted to said sleeve, a cutter carat one end with said shoe to limit the movement ried by said cutter arm, means to resiliently urge of the holder toward the piston, while the shoe is the free end of said cutter arm toward the gooseresting against the latter. neck of said bar, and means to variably limit the 6. In a tool for operating on pistons, a mem swing of the cutter arm. ber provided with a seat to engage the periphery 8. In a piston groover and scraper, a bar comof a piston, a carrier on said member adjustable prising a straight portion and a gooseneck, a from and toward said seat, a tool holder hinged sleeve slidable on the straight portion of said bar,

at one end to the carrier for swinging movements a cutter arm pivoted to said sleeve, a cutter carfrom and toward a piston engaged with said seat, ried by said cutter arm, means to resiliently urge means yieldingly pressing the tool holder toward the free end of said cutter arm toward the goosethe said seat, a shoe hinged to the carrier to neck of said bar, and an adjustable part assoswing about the hinge axis of the holder and ciated With the arm and adapted to engage the adapted to ride on the periphery of the piston, periphery of a piston in the gooseneck and therean adjustable member on the holder engaged at by limit the depth to which said cutter may exone end with said shoe tolimit the movement of tend below the surface of the piston.

the holder toward the piston, While the shoe is HERBERT A. BERKMAN. 

